What size is your tank and what do you have it stocked with?
Did you move around any rocks when adding the new fish?
C.afra as with other mbuna are harem breeders and should have at least 3 females for every male, a solitary female will often be singled out and either bullied or constantly pressed to mate.
Either your male is defending his territory from an intruder (the female) or he's trying to get her to mate whether she wants to or not.
My tank is 190litre, 50 gal, & is stocked with...
3 c.afra 1male 2female (turns out i have another female i didnt know off),
3 m.auratus 3female,
2 m.lombardoi 2female,
3 m.estherae 1male 2young,
1 p.socolofi 1young,
1 unknown small mbuna which i think female (will be posting pics soon for ID's)
and 5 peacocks of some sort (will be posting pics soon for ID's)
i do usually move rocks about when adding new fish, but at the same time as adding this female, i actually added more rocks so i didnt bother. maybe i should have done ? ...
ok, you know like i said earlier, ever since i added her, shes been constantly harassed, chased and having her fins nipped... well the past couple of days, ive noticed the male digging a den behind and under a big rock i have, he dont let any other fish near it, and earlier today, before i switched the light on, i was surprised to see him & the female together, looked like there were mating, in his den !!
after a cppl of minutes, they got disturbed, he chased off the 'intruder' and she waited in the den. he came back and they were at it again, im sure they were definately mating.
however that didn't last long, half an hour later and he's chasing her off again, and carrying on with his digging.
so i dont know what to do for the best ? is this normal, is it part of their mating ritual ? or is she being overly harrased and be best off being removed ? come to think of it... most of the females i have and have had, get treated badly of the males, except for a femle m.lombardoi i have that dont take sh*t of noone !!